1$Id: pvr2fb.txt,v 1.1 2001/05/24 05:09:16 mrbrown Exp $
2 3What is pvr2fb?
4===============
5 6This is a driver for PowerVR 2 based graphics frame buffers, such as the
7one found in the Dreamcast.
8 9Advantages:
10 11 * It provides a nice large console (128 cols + 48 lines with 1024x768)
12 without using tiny, unreadable fonts (NOT on the Dreamcast)
13 * You can run XF86_FBDev on top of /dev/fb0
14 * Most important: boot logo :-)
15 16Disadvantages:
17 18 * Driver is largely untested on non-Dreamcast systems.
19 20Configuration
21=============
22 23You can pass kernel command line options to pvr2fb with
24`video=pvr2fb:option1,option2:value2,option3' (multiple options should be
25separated by comma, values are separated from options by `:').
26Accepted options:
27 28font:X - default font to use. All fonts are supported, including the
29 SUN12x22 font which is very nice at high resolutions.
30 31 32mode:X - default video mode with format [xres]x[yres]-<bpp>@<refresh rate>
33 The following video modes are supported:
34 640x640-16@60, 640x480-24@60, 640x480-32@60. The Dreamcast
35 defaults to 640x480-16@60. At the time of writing the
36 24bpp and 32bpp modes function poorly. Work to fix that is
37 ongoing
38 39 Note: the 640x240 mode is currently broken, and should not be
40 used for any reason. It is only mentioned here as a reference.
41 42inverse - invert colors on screen (for LCD displays)
43 44nomtrr - disables write combining on frame buffer. This slows down driver
45 but there is reported minor incompatibility between GUS DMA and
46 XFree under high loads if write combining is enabled (sound
47 dropouts). MTRR is enabled by default on systems that have it
48 configured and that support it.
49 50cable:X - cable type. This can be any of the following: vga, rgb, and
51 composite. If none is specified, we guess.
52 53output:X - output type. This can be any of the following: pal, ntsc, and
54 vga. If none is specified, we guess.
55 56X11
57===
58 59XF86_FBDev has been shown to work on the Dreamcast in the past - though not yet
60on any 2.6 series kernel.
61 62--
63Paul Mundt <lethal@linuxdc.org>
64Updated by Adrian McMenamin <adrian@mcmen.demon.co.uk>
65 66